1. Field of the Invention
The present invention relates to a microscope stage used in a microscope, and more specifically to a microscope stage on which a sample mainly such as a living thing or living cell is placed, and which is moved so as to observe a desired section of the sample under microscope.
2. Description of the Related Art
Recently, the functional analysis of live cells is becoming widely popular. Among various functional analyzing methods, a so-called injection method in which a gene, fluorescent dye or the like is injected in a cell with a micro-needle and the behavior thereof is analyzed while observing the living cell or living thing, is carried out in the field of physiological researches.
In the case of this method, a cell (to be called “sample” hereinafter) is moved not only frontward, backward, leftward and rightward as ordinary methods, but also there is a demand of making it possible to move it horizontally along a rotating direction so as to determine the needle inserting direction.
A sample is moved as described above in any manner by means of the stage. However, in most of the cases of ordinary microscope stages, the movements in the frontward, backward, rightward and leftward directions are realized by moving each of the axes independently. For this reason, in most of the microscope stages, they can be rotated but the rotation center is always set at one point. With use of such a stage, it is not possible to smoothly carry out a series of operations as described above. In other words, in order to move the sample to a desired location, the movements in the frontward and backward directions, and the movements in the rightward and leftward directions must be carried out independently. Further, if a sample is to be rotated after it is moved to a desired location, the sample will move out of the view immediately after the sample is rotated, unless the sample can be rotated around the center of the view presently observed.
In order to improve such a drawback, a gliding stage such as shown in FIG. 1 has been proposed.
FIG. 1 is a diagram showing an example of an inverted microscope to which a gliding stage is applied. A gliding stage 102 is provided to a main body 101 of the microscope. The gliding stage 102 includes a disk-like upper stage 102a and a lower stage 102b. The upper stage 102a has a plurality of manipulation knobs 103 mounted thereto. On an upper surface of the lower stage 102b, a projecting portion 104 is provided along a circumferential direction of the stage. The upper stage 102a is placed such that the bottom surface thereof is brought into contact with the upper end of the projecting portion 104. Here, grease is uniformly applied on the bottom surface of the upper stage 102a. In this manner, the user is able to freely move the upper stage 102a placed on the upper end of the projecting portion 104 of the lower stage 102b by means of the manipulation knobs 103. With the slide resistance acting between the contact surfaces of the upper stage 102a and the lower stage 102b, the upper stage 102a is held such that it cannot be moved excessively in a horizontal direction. Thus, the user can rotate the upper stage 102a with the manipulation knobs 103, thus making it possible to rotate it horizontally around an arbitrary position.
Underneath the gliding stage 102, an objective lens 106 mounted to a revolver 105 is provided. Above the gliding stage 102, a condenser 107 and a lamp house 108 mounted to a post 101a are provided. Illumination light from the lamp house 108 is irradiated through the condenser 107 onto a sample 109 on the gliding stage 102, and then passes through the objective lens 106. In the end, an image is observed with the ocular lens 110. Then, with reference to the observed image obtained through the ocular lens 110, the upper stage 102a of the gliding stage 102 is moved by manipulating the manipulation knobs 103, and thus the sample 109 is moved to an appropriate position, where a needle 111 is inserted into the sample 109 to carry out an injection.
It should be noted here that in the case where the gliding stage 102 is manipulated, the operability of the upper stage 102a by hand is important. In the case of microscopic examination at a high magnification in particular, a very fine stage movement creates a large motion in the field of view. Therefore, it is difficult to move the sample 109 quickly to a desired location.
However, in the case of the above-described gliding stage 102, the manipulation of the upper stage 102a with the manipulation knobs 103 is to move the upper stage 102a by means of the manipulation knobs 103. This structure creates such a drawback that fine manipulations cannot be smoothly carried out. To avoid this drawback, the upper stage 102a is manipulated by placing a finger on the upper surface thereof, and the lower stage 102b is manipulated by placing another finger thereon, without using the manipulation knobs 103. In this manner, fine movements can be carried out relatively easily. However, in general, the upper stage 102a is made of a metal and the upper surface thereof is slippery. Therefore, there has been such a drawback that it is difficult to manipulate the stage by putting a fingertip on it, and the stage cannot be smoothly operated due to the loss created by a slipped portion.